Hitherto, network coding has been used as a mechanism for efficiently transmitting information on a wired network; at present, applying the mechanism (the network coding) to a wireless repeater (which will be hereinafter simply called repeater) is actively discussed.
FIG. 10 shows a wireless repeating system by a mobile station (MS) 71, a repeater 72, and an eNB (base station) 73. An operation example of network coding in the repeater 72 will be discussed with reference to FIG. 10.
Step 1: The mobile station (MS) 71 transmits data X to the communicating repeater 72.
Step 2: The eNB 73 transmits data Y to the communicating repeater 72.
Step 3: Repeater 72 XORs (exclusive ORs) the data X and Y and transmits data (X XOR Y) to the mobile station 71 and the eNB73 (hereinafter, data subjected to the processing will be called network coding data).
Step 4: The mobile station 71 grasps the data X transmitted by the station and thus can extract the data Y from the received data (X XOR Y).
Step 5: The eNB 73 grasps the data Y transmitted by the station and thus can extract the data X from the received data (X XOR Y).
In so doing, conventionally processing of transmitting the data X from the repeater 72 to the eNB 73 and transmitting the data Y from the repeater 72 to the mobile station 71 can be performed at a time, so that use efficiency of the frequency and the time can be enhanced.